Method of steam-heating.



J. L. FITTS.

METHOD OF STEAM HEATING.

APPLICATION FILED MAY 28. 1913.

an'uanto'c wi tmeooeo %'Wc/@ @d anMEs-LoGAN Errrs, oE PENSAUKEN 'rowNsHIr, CAMDEN COUNTY, NEw JERSEY, AssIcNoR 'ro WARREN wEBs'rER & COMPANY, A coRPoRA'rIoN or NEW JERSEY.

- METHOD OF STEAM-HEATING.

naeae.

Specification of Letters Patent.

Patented a a, raw.

Original application filed January 5, 1910, Serial No. 536,504. Divided and this application filed May 28,

' a 1913. Serial No. 770,293. 7, I

To all wkomit concern."

Be it known that I, JAMES L. Frr'rs, citizen of the United States, and resident of Pensauken township, county of Camden,

and State of New Jersey, have invented an Improvement in Methods of Steam-Heating, of whichthe following is a speclfication.

- This appliea'tionis a division of my application Serial Number 536,504, filed January 5, 1910, and has particular reference to the method of steam heating descrlbed' therein, said prior applicationlbeing specifimethod is carried out. o

My ventionfhas particular referenceto a method of steam heating in whlch low pressure steam is employed and 1n which the water of condensation is returned to the boiler by gravity; and the object of my ill-- vention is to provide a-system which shall-- automatically, duringthe normal operatlon of the heating system, permit the escape of air to the atmosphere, but which will pre-v ,vent the escape of water of condensation from the apparatus in, case of abnormal operating conditions, such as an excessive boiler pressure existing 1n the system:

More specifically, the object of .my in-:

' vention is to" provide a gravity system of steam heating which at all, times in normal operation is adapted to permit the air from the system to escape but without loss of steam or water, and to maintain these re sults irrespective of abnormal temporary conditions in the steam pressure of the' boiler. The object of my invention may therefore be stated to provide means which will automatically cause the steam heatingapparatus to provide a constant differential between the pressure in the steam supply and the return pipe, said constant differential'maintaining'a definite static head'on the return side, even where the steam pressure in the boiler is reasonably varied.-

My invention consists of certain improve- Referring to the'drawings: Figure 1 is v diagrammatic elevation of a steam heating.

cally directed to the apparatus in which the.

v radiators.

Fig, 2 is a sectional elevation of the automat c control valve used therein.

2 1s the boiler, and 3 are the steam mains leading therefrom and extending upward for this purpose may be employed. 6 are return pipes leading from the various radiators orv coils and are arranged to discharge at the. bottom intoa receiving tank 10 located at an elevation above the normal water line of1 the boiler 2. From the bottom of the receiving tank -10 the water is returned to the boiler by a pipe 9 connecti-ng with its lower part directly or through a check valve structure 8, which permits the flow of waterinto the boiler,

ut prevents the flow in'the reverse direction. Sometimes check valves are employed, and at other times they are omitted and in this latter' case the communication between the boiler and the tank .10 is -free and open. 7 are automatic valves of any suitable character for permitting the passage of air and water from theradiators 4 into the return pipes 6, but preventing or restricting the passage of steam. Numeroustypes of automatic valves adapted to steam heating apparatusar'e found upon the market, and any of these may be employed for the pur poses ofthe valves/Z, in carrying out the practice of my improved method. Opening from" the upper part of thetank -10 is a vent. pipe 11, preferably terminating in a check valve 12, said valve operating to perments which are fully described hereinafter v and more particularly defined in the claims.-

and consequently from the heating system,

and at the same time preventing the inflow of ,air in case of a partlal vacuum from any 10o cause, such as'when turning steam into cold turn pipe.

13 is an automatic valve device arranged in the pipe 11 and preferably between the tank 10 and the check valve 12, and operates automatically to control the pipe 11 to permit the escape of air, but prevent the escape of water, and therefore performs the function of retaining the water within the system, if from any abnormal cause the water tends to flow from the vent pipe into the atmosphere. The construction of this automatic valve. 13 is shown in Fig. 2, and comprises a thoroughfare 17 arranged in the vent pipe 11 and controlled by the valve piece 18. The valve piece 18 is secured to-a diaphragm 15 arranged as the sides of two, chambers 19 and 20, the former being in communication with the tank 10 through a pprtion of the vent pipe 11, and the latter ing .in communication with the steam supply pipe 3 by means of a small pipe 14. Normally, the chamber '20 is kept full of water so that the steam from the pipe 3 does not directly act upon the diaphragm 15 but upon the body of water within the chamber 20, and therefore indirectly upon the diaphragm. The diaphragm 15 is also connected to a rod 21, working through a stufiing-box in the bottom of the valve device, and said rod is hinged at its lower part to a counterbalance lever 16 having adjustable weights which permit of any degree of adjustment necessary. This weighted lever acts as a mechanical device for adjusting the normal pressure, upon the diaphragm 15, so that it shall properly respond to variations in the differential in pressures of the steam pipe 3 and the tank 10 or re- In the normal operation of the heating system, the level of the water in the tank 10 is above the level of the water in the boiler 2 sufiiciently to provide a static head to counterbalance the steam pressure carried in the boiler. and this may be, for example, 1% lbs, or any other low pressure, such as employed in low pressure steam heating systems. During the normal operation of the apparatus, the air is driven from the radiators 4 by the inflowing steam whose supply is regulated by the modulation valves 5, and

said air finds its way through the return pipe 6 into the receiving tank 10, and thence throughthe vent pipe 11, valve 13 and check valve 12, intoothe atmosphere. The water of condensation, which is produced within the radiators, is automatically permitted to fiow from the radiatorslinto the return pipes 6 by the automatic valves or traps 7, whenever said water accumulates. This water of condensation flows through the return pipes into the tank 10 and thence by reason of the static head, returns to the boiler.

sure in'the boiler, there will be danger of the water from the receiver tank 10 being forced outward through the vent pipe 11 into the basement or upon the floor of the building, producing not only an objectionable mess, but a more serious loss of water from the heating system and a variation of the diiferential between the steam supply and return sides of the system. This latter condition is particularly objectionable in an automatic gravity system, which is usually given but little attention. Whenever the boiler pressure increases abnormally, the water is not permitted to flow from the receiving tank 10 into it, because of the internal pressure which keeps the check valve device 8 closed; and consequently, the water of condensation passing from the radiators into the tank 10 will fill said tank and overflow through the pipe 11 if not otherwise prevented. Where the check valve device 8 is not employed, then the abnormal boiler pressure will force the water from the boiler through the pipe 9 into the tank 10 and thence outward through the vent pipe 11 if not prevented. The abnormal loss of water from any of these causes is liable to produce dangerous conditions in the system and a derangement of the normal working thereof.

By employing the automatic valve device 13 in the vent pipe 11, means is provided for maintaining the normal differential due to thestatic head and for automatically preventing the escape of water from the heating system under any of the abnormal conditions mentioned above.

In adjusting the apparatus, the weighted lever 16 has its weights so adjusted that the differential in pressures on opposite sides of the diaphragm 15 is such that the valve piece 18 will close the thoroughfare 17 when the receiving tank 10 becomes about half filled with water. In this way the vent pipe 11 will be closed by the valve device 13 before water enters the said vent pipe. This adjustment is due to the presence of a sufii cient pressure in the supply pipe 3 to cause the water in the pipe 9 and tank 10 to give a head above the water level in ,the boiler, such as would maintain the tank 10 about half filled with water. This would be a greater head than the normal head required; and any higher pressure in the boiler, which would cause a head of water being sustained in the pipes9 and 6 and tank 10, as would produce a discharge'of water through the vent pipe 11 if not otherwise prevented, could not produce such discharge because the valve device 13 would hold the vent pipe closed and build up an air pressure in the return pipe 6 and tank 10 which would prevent the rise of water into the pipe 11. While this should prevent rise of the water above the tank in normal operation, it is The valve device 13, as before stated, op-- erates under a difl'erential in pressure, the pressure below the diaphragm being the boiler pressure and that above the diaphragm being the pressure of the air and vapor in the return and practically atmospheric pressure. This atmospheric pressure is maintained largely because of the use of the automatic valve 7 from the discharge side of the radiators, as said valves restrict the passage of steam so that the returns are of a lower pressure than the steam pressure in the supply pipes 3. Any vapor in the returns is trifling in character when the valves 7 are properly constructed, and the normal pressure of said vapor is nominally that. of the atmosphere, because the valve device 13 in the normal operation of the apparatus is open and the check valve 12 ofi'ers no resistance to discharge into the atmosphere. I

VVhile' in the normal operation of the system, where the static head of water in the return pipe 9 exactly balances the steam pressure in the supply pipe 3, it is evident that the valve device 13 may be normally open to condensation from the radiators.

permit escape of any air which may find its way into the tank and the vent pipe 11, and which is brought down with the water of Steam. is not permitted to pass from'the radiators into the return pipes 6 and thence into the tank 10, because of the presence of the automatic devices or traps 7 which permit the free pas-' sage of water and air but restrict the passage of steam. As under these conditions we have a difi'ere'ntial corresponding to atmospheric pressure on the return side and the initial pressure of the steam on the supply side, there will be a constant flow of steam through the modulation valves 5 according to the requirements by the mere adjustment-of the valves. In view ofthe factthat when starting up the system with cold radiators'or when any radiator is su ddenly put into operation and a vacuum is produced therein, it

is evidentthat this is only a temporary condition and one which would. naturally tend to draw air from the outside into the system, and the check valve12 automatically acts to prevent the inflow of air under such conditions. This condition of vacuum, however,

does not impair the operation of the apparatus in the slightest, because the vacuum wherever it may exist is upon the return side ofthe modulation valves 5, and consequently the system will operate as a perfect heating system in which the Water will gravitate back to the boiler and the air which may be temporarily retained to a greater or less extent in the radiator, will ultimately be driven into the return pipe under the differential between the pressures in the supply pipe and the return pipe. Conditions of 5 vacuum could only continue where the condensing capacity of the radiators would be greater than the supply of steam delivered to them, "andwhile this is an abnormal condition for the operation of a system of this character, it is pointed out, however, that the system, being a closed and tight one which prevents the inflow of air from-the outside,

will operate during the presence of the vacuum in an automatic manner with great efiiciency during the continuance of the said vacuum. The operation of the apparatus under a pressure greater than that corre- 'sponding to the predetermined static head,

such as might occur by providing'toogreata boiler pressure from any cause unintentionally or otherwise, will cause the circulation of the steam under the same difierential, that is, equal to the predetermined static head due to the lower steam pressure, after the disturbance caused in the system by the raising of the steam pressure has had an opportunity to readjust itself, and this may be explained as follows: I Assuming that instead of 1% pounds of steam pressure, there was a 5 pound pressure, which with atmospheric pressure on the return side would make a diflerential of 5 pounds, which would support a static headof approximately tenfeet of water, and ms consequently the water would accumulate in the tank 10 and return pipe 6. As the increase in diiierential would cause the valv e. device 13.;to automatically close the vent pipe 11, no water would be permitted to '110 escape. In a short time, the accumulationsof air in the'return pipe driven into it under the steam pressure admitted to the radi-v ators, will build up a return pressure which will equal-the excess of the difi'erentialover Ill-2'; the predetermined amount, and by reason of this, the water in the return pipe 9 will flow'into the boiler and the water lowered, in the return pipe 6 and receiver tank 10 until the predetermined static head is once more established. This predetermined static head I is maintained, because .we now have only the 1;} pounds as a differential although we have 5, pounds steam pressure and "35} pounds back pressure in the return. This condition of the system is then exactly what it was originallydwhen we had 1% pounds steam pressure and atmospheric pressure inthe returns. As the governor valve 13 is adjustedjto automatically maintain a differ-" ential of 1% poundsbetween the steam supply and the returns, it is evident that it will operate with 5 pounds pressure in the supply to maintain the differential of 1?; pounds just the same as it would-operate with the steam pressure of 1% pounds. In fact, it will operate the same with any variation in the steam pressure, once the system has rebalanced itself, and at no time will it permit any'watergto pass, because no water would tend to pass except when there was a greater differential than l ipounds, and if the regulator or valve device 13 was set for that differential, it would not open the valve forany difi'erentialabove that amount. It is seen therefore, that my improved system is self-regulating and automatic and maintains the circulation of the steam under a definite differential, irrespective of the steam pressure in the boiler; and this en ables the system to be operated on the modulation principle in a perfectlycontrollab'le manner, for if the differential remains constant during normal operation of the system, the adjustment of the valve device will control the amount of heat which is to be given up by the radiators. It is therefore apparent that this system is responsive for variations in the steam pressure without derangement of the systemand will maintain its operation at a predetermined differential irrespective of the variations in the steam supply pressure; and moreover, by the use of the automatic Valve device 13 in the vent pipe, a constant operative static head may be employed to insure return of the water to the boiler by gravity for 'varilator or valve device 13 which is suitable i'forithe purposes of my invention, but I donot restrict myself to the use of any particularform of such a device, as any construction of, what is commonly known as a reduc- ,ing valve (similar in general construction to the valvedevice 13), may be used for the purposes of my improvements; and like- -wise, whilelhave shown a typical form of w pressure heatingapparatus, I do not estrict myself to the details thereof, as hese may bejvaried without departing from [the spirit r theinvention.

In this pplication, I make no claim to heapparatus herein shown and described, s that forms subject matter of my applica- 'tion of which this application is a division.

Having now described my invention, what 1 I claimvj'asnew and desire to secure by Letaf' .cter'sf Patent; i a

' 11. The herein described method of operat- .in g a;gravityo system of steam heating, which consists in providing a predetermined static head provided by maintaining a normal ter of condensation to the boiler said static head provided by maintaining a normal differential in pressures between the supply and return sides of the system with the return side open to the atmosphere whereby the steam may be delivered into the radiators under a predetermined normal difierence in pressures between the supply and return sides thereof, causing the water and air to pass from the radiators into the return side of the system while substantially preventing the passage of steam, and automatically controlling and preventing the escape of air from the return side of the system into the atmosphere when said normal differential in pressures in the supply and return sides of the system is exceeded whereby the air and water are retained in the return side of the system to build up an abnormal pressure whenever the steam pressure on the supply side exceeds a predetermined normal pressure corresponding to the normal static head in the return side, the operation being such that the air pressure added to the pressure due to the static head is made to balance the steam pressure on the supply side; and a constant operative differential in pressures above atmospheric pressure is maintained in the supply and return sides of the system for different boiler pressures.

2. The herein described method of operating a gravity system of steam heating, which consists in providing a predetermined static head on the return side for returning the water of condensation to the boiler said static head provided by maintaining a normal difierential in pressures between. the supply and return sides of the system with the return side open to the atmosphere whereby the steam may be delivered into the radiators under a predetermined normal difference in pressures between the supply and return sides thereof, causing the water and air to passfrom'the radiators into the return side of the system whilesubstantially preventing the passage of steam, automatically controlling the escape of air from the return side of the system into the atmosphere when the steam pressure becomes abnormal said control being under the regulation produced by said normal differential in the supply and return sides of t le system in such manner that the air and water are retained in the return side of the system to build up an abnormal premure whenever the steam" pressure on the supply side exceeds apredetermined normal pressure corresponding to the normal static head in the return side, and automatically causing all of the air in the return side in excess of that necessary to maintain this balance of pressures in the two sides of the system to escape out of the system, whereby the air pressure ressures in rim-at" J sures. I a 3. The herein described methodof operating a gravitysystemof steam heatin which consists in supplyingsteam from a boiler to the radiators and normally returning the water of condensation from the radiators to the boiler by gravity and under atmospheric pressure, maintaining astatic head in the return portion of the system for the purpose of balancing the normal pressure in the boiler, substantially preventing the fiow'of steam fromthe radiator on the return side, 1 of the systemwhereby a given normal pressure of air alone maybe formed in the return part of the system-between theradiator and down to the static head, and maintaining said ditferential'of pressures between the normal boiler pressure and return air res sure for all abnormalboiler ressures y a variable communication with t e-atmosphere on the return side of the system at 'a point between thestatic head and the radiators, fsaid communication controlled by the varia-- A boiler pressures a 4:. The herein descr bed method of operattion tfpiessures supply and return portions ofthe system and for all abnormal ing agravity system of steam heating, which consists in supplying'steam from a boiler to the radiators under apredetermined normal pres'lsure and; normally returning the water of condensation 'fromtlie' radiators t0 the boiler: bypgravity and under atmospheric pressure, causing the water and air'from the radiators to pass into the return pipe but preventing the passage of steam thereto, nor- -mally permitting the escape of the air to thhe t e atmosphere and deliverin the water to boiler, maintaining a static head onjthe return side of the system by the water in the return pipes to counterbalance the predewater to the atmosphere from the return pipe under the control of an abnormal steam pressure created in the'boiler.

v In testimony of which invention, I hereunto set my hand.

JAMES LOGAN FITTS. Witnesses: i I RrM HUNTER, R, M." KELLY;

: termined normal pressure in the boiler, and

automatically sealing the escape of air and 5O 

